package com.dapeis.im.tim.tls;

import java.util.Arrays;

import org.apache.commons.codec.DecoderException;
import org.apache.commons.codec.binary.Hex;

/**
 * @author 作者 E-mail: hzyuanyong@126.com
 * @version 创建时间：2017年5月17日 下午3:44:20
 * 
 */
public class TIMBase64 {

    static byte base64_table_url[] = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
	    'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U',
	    'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h',
	    'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u',
	    'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7',
	    '8', '9', '*', '-', '\0' };

    static byte base64_pad_url = '_';

    static short base64_reverse_table_url[] = { -1, -1, -1, -1, -1, -1, -1, -1,
	    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	    62, -1, -1, 63, -1, -1, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1,
	    -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,
	    13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1,
	    -1, -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
	    41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1, -1,
	    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	    -1, -1, -1, -1, -1, -1, -1, -1 };

    public static int unsignedToBytes(int b) {
	return b & 0xFF;
    }

    // int base64_encode_url(const unsigned char *in_str, int length, char
    // *out_str,int *ret_length)
    public static byte[] base64EncodeUrl(byte[] in_str) {
	byte[] out_str = new byte[1024];

	int out_current = 0;
	int current = 0;
	int length = in_str.length;

	while (length > 2) { /* keep going until we have less than 24 bits */

	    out_str[out_current++] = base64_table_url[unsignedToBytes((unsignedToBytes(in_str[current]) >>> 2))];
	    out_str[out_current++] = base64_table_url[unsignedToBytes(unsignedToBytes(unsignedToBytes(in_str[current]) & 0x03) << 4)
		    + unsignedToBytes((unsignedToBytes(in_str[current + 1]) >>> 4))];
	    out_str[out_current++] = base64_table_url[(unsignedToBytes((unsignedToBytes(in_str[current + 1]) & 0x0f)) << 2)
		    + unsignedToBytes((unsignedToBytes(in_str[current + 2]) >>> 6))];
	    out_str[out_current++] = base64_table_url[unsignedToBytes((unsignedToBytes(in_str[current + 2]) & 0x3f))];
	    current += 3;
	    length -= 3; /* we just handle 3 octets of data */
	}

	/* now deal with the tail end of things */
	if (length != 0) {
	    out_str[out_current++] = base64_table_url[unsignedToBytes(in_str[current]) >>> 2];
	    if (length > 1) {
		out_str[out_current++] = base64_table_url[unsignedToBytes((unsignedToBytes(in_str[current]) & 0x03) << 4)
			+ unsignedToBytes(unsignedToBytes(in_str[current + 1]) >>> 4)];
		out_str[out_current++] = base64_table_url[unsignedToBytes((unsignedToBytes(in_str[current + 1]) & 0x0f) << 2)];
		out_str[out_current++] = base64_pad_url;
	    } else {
		out_str[out_current++] = base64_table_url[unsignedToBytes((unsignedToBytes(in_str[current]) & 0x03) << 4)];
		out_str[out_current++] = base64_pad_url;
		out_str[out_current++] = base64_pad_url;
	    }
	}

	// System.out.println("length in base64EncodeUrl: " + out_current );
	byte[] out_bytes = new String(out_str).getBytes();
	return Arrays.copyOfRange(out_bytes, 0, out_current);
    }

    // int base64_decode_url(const unsigned char *in_str, int length, char
    // *out_str, int *ret_length)
    public static byte[] base64DecodeUrl(byte[] in_str) {
	// const unsigned char *current = in_str;
	int ch, i = 0, j = 0, k;

	int current = 0;
	int result = 0;
	byte[] out_str = new byte[1024];
	int length = in_str.length;
	/* this sucks for threaded environments */

	/* run through the whole string, converting as we go */
	// while ((ch = in_str[current++]) != '\0' && length-- > 0) {
	ch = in_str[0];
	while (length-- > 0) {
	    ch = in_str[current++];
	    if (ch == base64_pad_url)
		break;
	    /*
	     * When Base64 gets POSTed, all pluses are interpreted as spaces.
	     * This line changes them back. It's not exactly the Base64 spec,
	     * but it is completely compatible with it (the spec says that
	     * spaces are invalid). This will also save many people considerable
	     * headache. - Turadg Aleahmad <turadg@wise.berkeley.edu>
	     */
	    if (ch == ' ')
		ch = '*'; // never using '+'

	    ch = base64_reverse_table_url[ch];
	    if (ch < 0)
		continue;

	    switch (i % 4) {
	    case 0:
		out_str[j] = (byte) unsignedToBytes(unsignedToBytes(ch) << 2);
		break;
	    case 1:
		out_str[j++] |= (byte) unsignedToBytes(unsignedToBytes(ch) >>> 4);
		out_str[j] = (byte) unsignedToBytes(unsignedToBytes(unsignedToBytes(ch) & 0x0f) << 4);
		break;
	    case 2:
		out_str[j++] |= (byte) unsignedToBytes(unsignedToBytes(ch) >>> 2);
		out_str[j] = (byte) unsignedToBytes(unsignedToBytes(unsignedToBytes(ch) & 0x03) << 6);
		break;
	    case 3:
		out_str[j++] |= (byte) unsignedToBytes(ch);
		break;
	    }
	    i++;
	}
	k = j;
	/* mop things up if we ended on a boundary */
	if (ch == base64_pad_url) {
	    switch (i % 4) {
	    case 0:
	    case 1:
		byte[] error = new byte[1];
		error[0] = '\0';
		return error;
	    case 2:
		k++;
	    case 3:
		out_str[k++] = 0;
	    }
	}
	return Arrays.copyOfRange(out_str, 0, j);
    }

    public static void main(String[] args) throws DecoderException {

	// String hexString = "5095";
	String hexString = "789c6d8d4d4f83401884ff0b578c5dba0bbb98782015b1a1f8059a7222743fc8da96aecbdbdad6f8dfa5046fce6de6c9cc7c3bc522bfeec4baaa8dd1c2b9713c822e0a7ddfb91aa03c1a6d65552b90b6e794d2a0e7231c5a550d15b6ff96416fe590e38051c2281d732d640b5ae96172ea051c29be524c62e463e57382e854a08020a578c8febe38dfed5ba8e0642e9b98e21174bae97d16bfcde633299e0f49c81f27a26490b97665d7675dd0fdc35df1de994d23bc4301db349fbb918ea3e36b509878f7956d84dbb44b4ed23287b454f7119c12fea4968b64927d7c962179b9757e7e01ed1059d9";

	byte[] test = Hex.decodeHex(hexString.toCharArray());
	byte[] compressBytes = base64EncodeUrl(test);
	System.out.println("compress : " + new String(compressBytes));
	byte[] uncompressBytes = base64DecodeUrl(compressBytes);
	System.out.println("uncompress: "
		+ Hex.encodeHexString(uncompressBytes));
    }
}
